It is necessary for semiconductor manufacturers to determine, for example, a rated current, a rated voltage and a circuit configuration in designing a semiconductor device according to use of the semiconductor device and to provide parts and perform manufacture management according to a lineup of various semiconductor devices. Simultaneously, users are required to make preparations for and management of semiconductor devices for pieces of equipment. A semiconductor device has a number of semiconductor chips mounted therein. When even only one of the semiconductor chips is broken, a need arises to replace the entire device because it is difficult to make internal repairs in the device. The unit price of a semiconductor chip using SiC in particular is higher than that of an Si chip and replacement of the entire devices means a large loss. There has been such a high-cost problem. To cope with this, a semiconductor device in which two semiconductor modules are connected by a wiring bus bar has been provided (see, for example, Patent Literature 1).